When, a few minutes later, local police and state troopers arrived at the Hilltop Drive home where the call came from, they found Svetlana Bell, a 47-year-old violinist and music teacher, unresponsive on the kitchen floor, with her teenage daughter frantically trying to revive her.

His compact, .380-caliber Keltec pistol hung in its holster on a chair, and on the floor, near where his wife lay, was a kitchen knife. Four bullet casings were scattered through the kitchen and adjoining living room.

On Wednesday, a jury in state Superior Court will begin hearing the testimony that will help them decide if the 64-year-old ham radio enthusiast meant to cause serious physical injury when he shot his wife, or whether he was protecting himself from a woman in the midst of an emotional crisis who was waving a knife and advancing toward him.

Bell's attorney, John Gulash, of Bridgeport, plans to call a half-dozen witnesses, including one of Bell's friends and two firearms experts, to prove his claim that the shooting was an act of self-defense.

But none of the defense witnesses are likely to be as crucial as the couple's daughter, who is now 18. She saw her father kill her mother and observed the events leading up to the tragedy.

In a six-page statement given to investigators a month after the shooting, Elizabeth Bell describes a household where other family members virtually walked on eggshells around her mother, who she said had "serious emotional issues" and trouble controlling her anger, which could "quickly escalate into violent rages."

Even loud noises, or someone accidentally dropping something, could set her off, the daughter said.

If her father wasn't at home when her mother got angry, Elizabeth said, she would run into her room, "climb to the top bunk, and pull the ladder up with me so she couldn't reach me."

But on other occasions Svetlana Bell, an elementary school music teacher in Wilton who played violin with the Danbury Symphony Orchestra, was "a very kind, loving person, and she cared a lot about my father and me.

"When she wasn't angry, she acted like a normal person who would never want to say or do the things that she did or said," the daughter told police.

In contrast, Robert Bell was " a very calm, caring person" who didn't anger easily and tried to settle things down when an argument broke out, she said.

Elizabeth Bell told state police Detective Rachel Van Ness that the deadly confrontation was triggered when Robert Bell tried to assist his wife in making popcorn while the family watched a recording of the British TV drama "Doc Martin."

A few minutes earlier, she said, her mother had grabbed a knife off the counter and began making "violent, stabbing motions at my father," but he managed to calm her and she put the knife down.

But when her mother appeared to be distracted and her father again tried to help, another argument broke out.

"She told him to get out of the way, and he said he wasn't in her way," Elizabeth said. "She grabbed the knife and made the same violent motions while approaching him."

Robert Bell retreated, she said, then "everything happened so quickly. ... I suddenly saw a gun in my father's hand and several flashes."

As Elizabeth attempted to perform cardio-pulmonary resuscitation, Robert Bell called for help.

"I remember my father telling the dispatcher to hurry, and he kept saying, `Oh, God,' " she said.

Gulash declined comment Thursday, telling The News-Times "it would be inappropriate to say anything so close to trial."

Initially, state police sought to charge Bell with murder, but state prosecutors opted for first-degree manslaughter, which refers to a homicide committed under the influence of extreme emotional disturbance.

When testimony gets underway, Assistant State's Attorney Sharmese Hodge will try to prove that Bell had other options, short of shooting his wife, to stop her.

Documents filed by the prosecution allege that Svetlana Bell's arm bore a bruise inflicted by her husband, indicating he'd made physical contact with her, and that in contrast to Elizabeth Bell's description of him as nonviolent, he'd exhibited "irrational behavior" toward his daughter for an unspecified mistake and that he'd once used a firearm to harass a neighbor.

Hodge also claims that Bell's instructions to his daughter not to tell police anything after they'd arrived showed a "consciousness of guilt."